It is our hypothesis that mediators of the inflammatory response(cytokines) induce increased gut permeability in IBD and that the increase in gut permea-bility is related to the severity of disease and the degree of inflammatory reponse. Further, the increased gut permeability in IBD, by increasing endo-toxemia, tends to exacerbate and perpetuate the inflammatory bowel disease and its extraintestinal manifestations. In this study we will evaulate the role of cytokins, alterations of gut perm. & the systemic inflammatory response in IBD.